Rogue Engineering is proud to introduce its Diablo TRACK exhaust for the 2001-06 E46 M3!
Having our Rogue Engineering Carbon Widebody Test Vehicle at the track testing products on a regular basis allowed us to continually develop, design, dyno, re-develop and ultimately produce a great sounding, performance exhaust for those looking for the most out of their E46 M3 going to the track. During the design phase, we wanted to address a certain amount of criteria:Free flow, but without the torque loss.
When developing a track-specific exhaust for the E46 M3, we noticed that other available exhaust systems go with the bigger-is-better route. By merging the exhaust pipes after the bottom of the headers, and dumping it into a huge 3.5" diameter pipe, you get big sound and improved top end HP, while sacrificing lower end torque.
Our exhaust actually begins after the E46 M3 midpipe (aka Section 1). While others that produce an exhaust that starts just after the end of the exhaust manifolds and immediately merge the exhaust pipes into a "Y" pipe, we found in our testing that the exhaust gas velocity is severely hampered by this "traffic bottleneck". While you spend big money trying to select the best S54 header for your car, that decision is quickly extinguished as you immediately merge the exhaust pipe together immediately after the header itself. We found that even after the Section 1 that the exhaust gases velocity had slowed only a little, which made merging the exhaust pipe a better.
The real test was on our dyno
, where we could see the performance gains. To keep things as consistent as possible, these tests were performed on the same vehicle.
The first dyno graph shown above is a comparison between a "street performance" exhaust (OEM Euro headers, stock section 1 and 2, aftermarket software, Eisenmann Race rear muffler) and a traditional 3" track exhaust on our E46 M3 test car. It makes some good power, but obviously, this is designed for a street car. The traditional 3" track exhaust replaces the "street performance" section 1, 2 and rear muffler removed and replaces it with a single tube exhaust, with a merge after the exhaust manifolds.
As you can see, there is an expected improvement in hp and torque from the single 3" exhaust after 5000rpm. Upon closer inspection, there is a DECREASE in hp and torque below 5000rpm. More importantly, there is an approximately 64 ft lb. LOSS of torque at the rear wheels at approximately 3400rpm. Some would argue that since this is a track specific exhaust that this acceptable since most of the time one would expect to be in the higher RPMs anyway (or hope to be). The reality is that if you're coming out of a corner at the track below 5000rpm, you're at a disadvantage.
The second dyno graph shown above is a comparison between the aforementioned traditional single-pipe track exhaust and Rogue Engineering's Diablo TRACK exhaust.
Of course, the traditional track exhaust has shown a HP and torque improvement over street components (while sacrificing performance below 5000rpm). However, with Rogue Engineering's Diablo TRACK exhaust, not only do we see a slightly improve the top end performance, but we show a max torque differential of approximately 80 ft. lbs at 3400 compared to a traditional single-pipe track exhaust! Have your cake and eat it, too! This means having that all-so-important additional torque at the wheels coming out of corners while benefiting from the top end power on the straights!
How about one last dyno chart for fun?
This last chart is one from an unrestricted, retired, Continental Challenge Grand-AM GS car (E46 M3) with a $25,000 blueprinted S54 (engine dyno verified at 420hp) running Bosch Motorsport electronics (entire wiring harness and computer), tuned by a Bosch engineer. The exhaust on the vehicle was a 3" OD, single exhaust with a single muffler on the end. Like many of the track exhausts out there, it also had a merge collector (produced by Burns Stainless) right after it's OEM Euro E46 M3 headers. As per the rules, the car uses an OEM airbox.
Like the other single tube track exhausts, torque was just not there below 5000rpm. After the RPMs got up high (6600rpm), it is clear to see that between the blueprinted engine, Bosch electronics and custom tuning that it has top end power. Then again, most professionals tend to keep them at the limit most of the 2.5 hours during the race.
This power is not just about the position of the merge collector. During testing, when we positioned the rear muffler so that there were virtually no bends, there was not enough backpressure in the system and did not produce enough torque at the wheels.
The Rogue Engineering TRACK exhaust has been engineered to have two 90° bends in its 3" diameter tubing; one before the muffler and one directly after. These two bends proved to be a critical during the development as they added much needed backpressure to the system. Combine these with the custom-made, Rogue Engineering straight through muffler design and you have a free-flowing exhaust with enough backpressure to extract more HP without sacrificing torque! Lightweight, strong and simple.
Pie-cut exhaust tubing and v-band clamps are all the rage in custom, high end exhaust systems. However, once you get over the awe and drool over those features, it's time to get to serious. Our Diablo TRACK exhaust has strength and simplicity in mind while providing reliable, proven components in it's construction.
When welding exhaust tubing, done correctly, the weld turns out to be the strongest portion. During the welding process the tubing near the weld becomes more fragile and weaker, because of the heat. For a track car that sees mostly high rpm and heat most of its life, the exhaust will spend most of the time with high heat in it. To minimize the potential of cracking tubing and increase strength, we chose to mandrel bend as much of our exhaust as possible, and to minimize TIG welded portions of the exhaust.
Where's the tip? We chose for the exhaust to terminate with it's 3" diameter tubing just past the bumper opening on the right side of the vehicle. If you like the simple, understated look, just leave it. If you desire something fancy, just modify the end and weld one on. No sense in making the exhaust more expensive with a tip you may or may not like. Besides...most people looking at it will be behind you!
3-bolt flange vs. V-band? As you will see towards the front of the exhaust, we have added a 3-bolt exhaust flange. It is designed to bolt up to a portion of our Rogue Engineering E46 M3 X-Pipe
section (Version 2). Having this 3-bolt flange ensures that when bolting it together correctly that the exhaust is eliminate fitment issues. Lining up the flange improperly would make it impossible to install. If a V-band flange was used, it allows for minute adjustments which can turn the exhaust orientation as little as a fraction of a degree, causing potential problems such as interference/hitting with the body and with suspension components. By using this, we are trying to make the installation process simplier.
Like the factory exhaust, we have incorporated an integrated heat shield to protect the left side axle boot from unwanted heat. This is a small, but necessary detail for a track exhaust which sees a lot of heat.
More volume, but refined sound.
Because of the modular design of the system, you can tune the sound of the exhaust to your needs.
- Using catalytic converters in Section 1 before the exhaust (such as OEM Euro cats) will give you the quietest combination.
- Using a RASP mid pipe in Section 1, will give you a slightly toned down sound.
- Using a straight pipe Section 1 (or removing the single resonator of the factory Section 1), will allow you to announce your arrival in your neighborhood for miles around, as this will be the loudest combination.
Use of the system requires our "Y" connector pipe shown. This is the same "Y" connector found on our Rogue Engineering E46 M3 X-Pipe (Version 2),
so for those that already have the X-Pipe, you do not need to purchase the "Y" connector.
Rogue Engineering Diablo TRACK Features
- 100% T-304 stainless steel, mandrel bent and full TIG welded construction.
- Lightweight at just 35 lbs. (with Y connector), 43 lbs. lighter than the OEM Section 2 and OEM rear muffler.
- NOT compatible with vehicles that have installed a fuel cell in the trunk.
- Legal for all BMW CCA race classes as well as many SCCA classes.
Installation and Application Notes: While this is designed to be a track-specific product, this product may not meet (and does not claim to be) decibel restrictions at tracks with specific noise regulations such as Lime Rock Park, Mt. Tremblant, Laguna Seca, Sears Point, and others.
This product fits the following vehicles: